Wireless Roaming; Power Save Polling; Qos - Extreme Networks Summit WM3000 Series Reference Manual

NOTE
Port adoption per controller is determined by the number of licenses acquired.

Wireless Roaming

The following types of wireless roaming are supported by the controller:
Intercontroller Layer 2 Roaming
●
Intercontroller Layer 3 Roaming
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International Roaming
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Intercontroller Layer 2 Roaming
An associated MU (connected to a controller) can roam to another Access Point connected to a different
controller. Both controllers must be on the same Layer 2 domain. Authentication information is not
shared between the controllers, nor are buffered packets on one controller transferred to the other. Pre-
authentication between the controller and MU allows faster roaming.
Intercontroller Layer 3 Roaming
Intercontroller Layer 3 roaming allows MUs to roam between controllers which are not on the same
LAN or IP subnet without the MUs or the rest of the network noticing. This allows controllers to be
placed in different locations on the network without having to extend the MU VLANs to every
controller.
International Roaming
The wireless controller supports international roaming per the 802.11d specification.

Power Save Polling

An MU uses Power Save Polling (PSP) to reduce power consumption. When an MU is in PSP mode, the
controller buffers its packets and delivers them using the delivery traffic indication message (DTIM)
interval. The PSP-Poll packet polls the AP for buffered packets. The PSP null data frame is used by the
MU to signal the current PSP state to the AP.

QoS

QoS provides a data traffic prioritization scheme. QoS reduces congestion from excessive traffic.
If there is enough bandwidth for all users and applications, then applying QoS has very little value.
QoS provides policy enforcement for mission-critical applications and/or users that have critical
bandwidth requirements when the controller's bandwidth is shared by different users and applications.
QoS helps ensure each WLAN on the controller receives a fair share of the overall bandwidth, either
equally or as per the proportion configured. Packets directed towards MUs are classified into categories
such as Management, Voice and Data. Packets within each category are processed based on the weights
defined for each WLAN.
The controller supports the following QoS mechanisms:
Summit WM3000 Series Controller System Reference Guide
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